CVE-2005-1108 in Internet Junkbuster
Summary
by MITRE
The ij_untrusted_url function in JunkBuster 2.0.2-r2, with single-threaded mode enabled, allows remote attackers to overwrite the referrer field via a crafted HTTP request.
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Analysis
by VulDB Data Team • 06/06/2019
The vulnerability identified as CVE-2005-1108 affects JunkBuster version 2.0.2-r2 when operating in single-threaded mode, presenting a significant security risk through improper handling of HTTP request parameters. This flaw resides within the ij_untrusted_url function which processes incoming web requests and fails to properly validate or sanitize the referrer field data. The vulnerability manifests when remote attackers craft malicious HTTP requests designed to exploit the function's inadequate input validation mechanisms, potentially leading to unauthorized modification of critical web traffic metadata.
The technical implementation of this vulnerability stems from a lack of proper input sanitization within the JunkBuster proxy server's request processing pipeline. When single-threaded mode is enabled, the server processes requests sequentially without adequate protection against malicious input manipulation. The ij_untrusted_url function specifically fails to properly validate the referrer field, allowing attackers to inject crafted data that overwrites existing referrer information. This represents a classic case of improper input validation where the application accepts untrusted data without sufficient sanitization, creating a path for malicious actors to manipulate the referrer header that is typically used for security and tracking purposes.
The operational impact of this vulnerability extends beyond simple data manipulation, potentially enabling sophisticated attack vectors including web cache poisoning, session hijacking, and cross-site request forgery exploitation. Attackers can leverage this flaw to inject malicious referrer data that may bypass security controls, manipulate user sessions, or redirect traffic to malicious destinations. The single-threaded mode exacerbates the risk as it reduces the system's ability to properly isolate and validate incoming requests, creating a more vulnerable processing environment where a single malicious request can affect the entire system's integrity. This vulnerability particularly impacts organizations relying on JunkBuster for web filtering and security, as it undermines the trust model of the proxy server's traffic handling mechanisms.
Mitigation strategies for this vulnerability require immediate implementation of input validation measures and system configuration changes to address the root cause. Organizations should upgrade to JunkBuster versions that have patched this vulnerability, as the original 2.0.2-r2 release contains known security flaws that have been addressed in subsequent releases. Configuration changes should include disabling single-threaded mode when possible, implementing strict input validation for all HTTP headers, and deploying additional network security controls such as web application firewalls to monitor and filter malicious requests. The vulnerability aligns with CWE-20, which catalogs improper input validation as a fundamental security weakness, and could be categorized under ATT&CK technique T1071.004 for application layer protocol manipulation. Security monitoring should focus on unusual referrer header patterns and anomalous HTTP request behaviors that might indicate exploitation attempts, while access controls should be strengthened to prevent unauthorized modification of proxy server configurations that could enable similar vulnerabilities in other components of the web filtering infrastructure.